Regenerative open-hearth furnace



May 29, 1928. 1,671,100

s. J.- coR-r Er m.

REGENERATIVE-OPEN HEARTH FURNACE Filed Dec. 21, 1925 5 Sheets-Sheet 2 gm is:

z'wm We er and af'le o la@ v Patented May 29, 192.8.

UNITED STATES PATENT OFFICE..

vSTEWART J. CORT, F BETHLEHEM, PENNSYLVANIA; TIMOTHY BURNS, 0F BUFFALO,

` NEW YORK; -AN D ROBERT S. A. DOUGHERTY AND CHARLES E. LEER, OF BETHLE- HEM, PENNSYLVANIA, ASSIGNORS TO BETHLEHEM STEEL COMPANY, OF BETHLE-- HEM, PENNSYLVANIA, A CORPORATION OF- PENNSYLVANIA.

nnennnna'rlvn OPEN-amara summon,

Application led December 21, 1923. Serial No.- 681,939.

Our invention relates to regenerative furnaces and it hasY for an object to provide damper controlled throats for furnaces of the character referred to with water-cooled or heat resistant liners in order to prolong the life of the throats. v IA further object of our invention is to provide a damper entrance slot in the roof of a furnace of the character referred to, the walls of the slot having cooling means therefor.

A further object of our invention is to provide pairs of water-cooled beams in the roof of a -furnace of the character referred to, the beams of each pair being spaced apart sufficiently to define a damper entrance opening and the beams of each pair being secured to opposite sides of an opposed pair of buckstays. v p

A further object of our invention is lto provide pairs of spaced beams, the beams of each pair being secured to opposite sides of an opposed pair of buckstays and having secured therebetween the .upper ends of water-cooled liners'for throats of ,a furnace and the space between the'beams and between the upper ends of the liners servin as a damper entrance opening.

A further object of our invention is to provide a furnace of the character referred to having dampersmovable through openings in the' furnace roof with hoods extending above the roof in order to constitute pockets to receive the dempers and to minimize the leakage of gases by the dampers toithe ex= terior of the furnace.

Apparatus" made in accordance with our invention is illustrated in the accompanying drawings, forming a part of this application, in which:

Figure 1 is a fragmentary and longituu dinal sectional view of a furnaceembodying features of our invention;A

Figure 2 is a transverse sectional view taken along the line H-H of Figure 1;

Figure 3 is a fragmentary` plan view of the. apparatus illustrated in Figure 41;

Figure d is a sectional view of a damper; Fi ure 5 is a transverse sectional view of the amper rim;

Figure 6 is a detail view of fastening 4taken along the line means for securing the damper hood in place; i Figures 7 and 8 are detail views of fastening means for the damper hood cover;

Figure 9 is a horizontalsectional View IX-'IX of Figure 1; Flgures 10, 11 and 12 are detail views showing features of our improved Watercooled throat liner; and,

Figures 13 and 14 are detail and fragmenary views of our improved roof beam strucure. Referrinnow to the accompanying drawings for a etter understandlng of our invention, we show a furnace or melting chamber, at 10, which is comprised by the hearth 11, parallel' side walls 1,2, converging end walls 1 3, and a roof' section 14, and end chambers, at '15, comprised by bottoms, 16, converging side walls 17 and roof sections 18. The side walls 13 and 17 at each end of thefurnace converge in opposite directions and are connected by the knuckles 19. The end chambers serve in a wellf known manner as mixin or combustion chambers, gas being su plled thereto by the gas uptake 20`and air eing supplied thereto by-the air uptake 21.,

The effective area of the throat aordin communication between the end chambers 15 and the furnace chamber 10 is varied or controlled by means of a transversel movabledamper 23, which is movable t rough an opening in the roof of the furnace by a cable Qtpaesing over a sheave 25, the cable being connected .to any suitable operating mechanism well-known to those skilled in the art and constituting no part of ourv present invention'.v

The damper illustrated is of a'vtype old in the art and it preferably comprises a central body or core of refractory material consistingofbrickwork 26 surrounded by a Water-cooled frame 27, the latter being supplied with a perforated tube 28 connected to a source of compressed air and serving to stir 11p-sediment in the frame 27. The frame is connected by tubes 29'and 30 to a cross hat 31, the latter being attached to the cable 24 already referred to. The tubes 29 and 30 also serve as outlet conduits for g sa the rims, such tubes being connected to a common conduit 32 and the latter communicating b a hose connection 33 with a conduit 34 lcading to the exhaust collector 35. The tube 29 has arranged therein a smaller tube 36 which communicates'with a flexible hose section 37 ,fthe latter being coupled to a conduit 38 leading to a Water supply manifold 39. The other conduit 30'encloses a smaller conduit 40 connected by a hose 41 to a conduit 42 leading to a suitable supply of compressed air.

The knuckles 19 at the ends of the furnace are provided with vertical liners 44 which are oblong box-like metallic receptacles provided with water inlets 45 connected to tubes 46 terminating near the bottoms of the box-like receptacles. The inlets 45 are connected to conduits 47 leading to the supply manifold 39. Each liner is provided with an outlet 48 at its upper end and the outlets are connected to discharge conduits 49, which lead to the exhaust rcceiver 35. I

The lower ends f the liners 44 are held in place in suitablerecesses 50 in the floor or bottom 16 and preferably fit against shoulders 51 provided at the side walls of the throat 19. The upper ends of the liners are arranged between transverse roof` beams 53, to `be more particularly hereinafter d escribed. The liners are referably provided with laterally extende vertical ribs 54 which fit corresponding vertical grooves 55 in the beams 53. From the structure described, it will bc apparent that our improved liners 44 are readily removable from the furnace, it 'being only necessar to detach the conduit connections 47 an 49 and lift the liners upwardl The pairs of cooperating beams 53 de ne damper entrance spaces 56 for the dampers 23 and serve to support the roof sections 14 and 18 in a manner to be referred to.

Each of the beam sections 53 is preferably L-shaped for the major portion of the len th thereof and each section is provided wit communicating with the manifold 39 and discharging to the exhaust receiver 35, the conduits being arran ed near the surfaces of the beams which efine the damper entrance opening and near the bottom sides Vof the beams which are exposedto the heat of the furnace so asV to effectively cool the beams and to oppose burning out thereof due to the heat of the furnace.

The bea-ms 53 are opposite and complementary in design so as to provide the damper entrance openings 56 and opposed vertical slots 55 to receive thetongues 54 of the liners. Outside of the liners, 'the beams are provided with attaching ortions 58 which are adapted to be attachediy bolts water cooling conduit openings 57.

beams 53 of a pair may furthermore be secured together by suitable bolts or keys 61.

As illustrated, the pairs of beam members 53 are arranged to extend transversely of the furnace above the throat portions thereof, such throat portions being provided by opposed reentrant or monkey walls comprised by the converging wall portions 13 and 17 The buckstays 60 are arranged exteriorly of the furnace an fit against the outside of the reentrant walls and serve to reinforce the latter. In addition to the buckstays 60, the furnace is also equipped with other buckstays 63 spaced Wider apart for reinforcing the Walls of the furnace.

Thebeam structures, comprised-by the pairs of complementary beam members 53 serve to divide the furnace roof into a plurality of sections, whereby a section maybe removed or repaired without disturbing other sections. Where the roof of the furnace is a unitary piece of masonry construction, it will bc apparent that vrepairs and replacements cannot be localized to isolated sections but that the entire roof must generally be replaced.v Our transverse beam' structure, therefore, affords a roof construction such that the end sections 18 may be replaced or repaired Without affecting the central section 14, andthe latter section may be removed or repaired without affecting the end sections. As illustrated. the roof section 18 is inclined slightly downwardly toward thc furnace chamber 10, whereby lateral thrust is imposed upon the transverse beam structure. The transverse beam structures, therefore, not only serve to isolate the roof into a plurality of sections but also serve to support or resist any lateral thrusts incident to the design of the roof sections. v

In order to minimize the leakage ofgases through the space 56 and around the damper Wei-provide a hood at 65, which extends above the roof of the furnace and constitutes a pocketl or receptacle for enclosing the damper when the latter is elevated. lThe h-ood is preferably,comprised by ametallic shell 66 which embraces refractory material 67, the latter defining a damper pocket or receptacle 68. The shell 66 is provided 'with flange means 69 .at the bottom, the Aflange means 69 resting on the beams 453 and being preferably secured to the latter by detachable key means 70, such as illustrated in Figure 6. The key means referred 1.o may be comprised by bolts 71 which pass through openings 72 in the beam members 53 and registering openings 73 in the flange means 69, the bolts being provided with transverse slots to receive Wedge keys 73. From the structure described, it will, therefor be apparent that the hoods 65 maybe readily attached and detached from the or rivets 59 to opposed buckstays 60. The beam structures.

The shells 66 are preferably provided' with flanges 75 near the tops upon vvwhich fit the top sections 76, the latter being notched` at 77 to receive L-shaped keys 78 ittino' in openings 79 in the flanges 75 and hel in/ place by transversely extending wedges 8O as v shown in Figure 8. The cover-for the hood is preferably made in complementa] sections h burn out.l It will also be a parent that we vas ' to the inner sides of the mon have provided transverse earn structures which are water-cooled, suchv beaml structures serving to define damper entrance openings, to Ydivide the furnace roof into a pluralit of sections and to serve as tying means or opposed buckstays 60the latterv cooperating to afford lateral support l for the reentrant monkey walls. In addition, it will also be seen 'that we provide av hood construction for they damper, whereby only openings for the lconduits 29 and 30 must be provided and the-leakage of gas around the damper to the outside is effectivel` limited.

While we have shown our invention in but one form, it will be obvious to those skilled in theart that it is not so limited, but is susceptible of various other changes and only such limitations shall be placed thereupon as are imposed by the prior art or as are specifically set forth in the appended claims. Y

Having thus described the invention, what we claim as new and desire to secure by LettersPatent is g 1 In a regenerative furnace, in combination. inwardly extending Walls defining'l a throat and water-cooled members disposed entirely to the inner sides of and cooperating with the innermost portions' of said walls. A

2. In a regenerative furnace, in combination, inwardly-projecting monkey walls and vertical water-cooled liners dis osed entirely ey Walls.

'3. In a regenerative furnace, in combination, inwardly-projecting monkey walls, water-cooled liners disposed entirely-to the inner sides of the monkey walls, 'i and a damper movable between the liners. f

4. In a regenerative furnace, in combination, inwardly-projecting monkey walls,

`tion, reenti'ant side walls,

buckstays cooperatingv exteriorl 'with the innermost portions of said wal s, a vWatercooled beam structure carried' by opposed buckstays and defining a. damper slot, and a damper movable through the slot and be- 't-Ween the monkey walls.

5. In a regenerative furnace, in combination, end passages, dampers for the passages, pairs of opposed buckstays, yand watercooled lmeans connected to opposed buckstays and defining entrance spaces for the -dampers 6. In a regenerative furnace, in combination, end passages for the furnace including monkey walls, vertical water-cooled liners disposed entirely to the innersides of the 'monkey walls and cooperating with the innermost portions of said Walls, a damper having a WaterLcooled frame and movable between the liners, and an entrance slot for `the damper having water-cooled walls.

7. In a regenerative furnace, in combination, end passages, dampers for the passages, pairs of opposed buckstays, and Water-cooled beams connected to the buckstays and defining, entrancev spaces for the dampers.4

8. In a regenerative furnace, in combination, end passages, dampers for the passages, pairs of opposed buckstays, Water-cooled beams connected to the buckstays and defin- -in'g entrance spaces for the /dampeizn and hoods for 'the dampers carried by the beams.

9. In a regenerative furnace, in combinaltion. end passages, dampers for the passages,

pairs of opposed buckstays, Water-cooled beams connected to buckstays and defining entrance spaces for the dampers,"hoods for the dampeisand means for detachably conl necting the hoods to the beams. modifications without departing from the spirit thereof, andwe desire, therefore, that 10. In a regenerative furnace, in combinalos tion, end passagesdampers for the passages,

pairs of opposed buckstays and pairs of horlzontal beams constituting parts of the roof, each pair of beams being secured to a pair of opposed buckstays and defining a damper entrance space.

11. In a regenerative furnace, in combinawith the. side walls, buckstays arranged exteriorly of the reentrant portions, a pair' of beams carried b v the buckstaysand definmg Va damper entrance space', and a damper mov-- a roof cooperating for portions of the reentrant Walls nearest to each other, a Water-cooled beam structure in the roof' and having a damper entrance damper having a vvateropening, and a the liners and cooled rim arranged between movable through the opening.

1.4. In a regenerative furnace, in combination. end portions including side walls and roofs, buckstays for reinforcing the sidewalls` a pair of transverse beams secured to opposed buckstays and in the roof of meh end portion, the beams of each pairbeing spaced apart to define a damper entrance opening.v a damper for each opening, and heat resistive side wall liners opposite to the vertical edges of each damper and having their upper ends secured between the beams of a pair.

15. In a regenerative furnace, in combination, side walls, a roof, a hearth, the side walls converging and then diverging beyond theV ends of the hearth, a series of pairs of buckstays cooperating with the side Walls, including inset pairs cooperating with said walls near the ends at points of greatest con- Lenfoo tween the beams of the pairs, the space be tween the beams and between the liners constituting' a damper entrance space, and a damper movable through said entrance space and between the liners.

In testimony whereof our signatures.

This 5th day of December 1923.

STEWART J. CORT., This 8th day of December 1923.

' TIMOTHY BURNS. This 7th day of December 19:23.

ROBERT S. A.. DOUGHERTY. This 13th day of December 1923.

v CHAS. E. LEHR.

we hereunto alix 

